The present invention relates to basic aluminum antiperspirant active materials containing univalent complex oxoanions, antiperspirant active compositions including such basic aluminum antiperspirant active materials and also containing another antiperspirant active salt such as a zirconium, hafnium, titanium and/or tin salt, and methods for producing such materials and compositions. The materials and compositions of the present invention have a wide range of application as antiperspirant materials, including, for example, as antiperspirant active agents in aerosols, roll-ons, solid sticks, and other known systems for delivery of antiperspirant materials to, e.g., the axillary region of the human body.
The present invention is particularly directed to basic aluminum antiperspirant materials containing a univalent complex oxoanion of nitrogen or halogen, antiperspirant compositions containing such materials, and methods of making such materials and such compositions.
In conventional basic aluminum halides, including those having enhanced activity, aluminum metal has been added in excess to a solution of the aluminum halide salt, since it is known in the art that the formation of conventional basic aluminum halides requires a level of aluminum metal, to be added to a solution of monomeric aluminum halide, that is in excess of that required by reaction stoichiometry. According to Fitzgerald, "Chemistry of Basic Commercial Aluminum Hydrolysis Complexes" in Laden, et al, Antiperspirants and Deodorants (1988), page 219, aluminum metal is added in a two- to four-fold excess. If aluminum metal is not added in such excess, aluminum metal will not solubilize rapidly, the aquated aluminum ions will not hydrolyze sufficiently nor achieve a sufficiently high level of aggregation, and the desired end product will not be formed within a commercially feasible time frame. Aluminum metal may be added in stoichiometric excess in order to ensure a large aluminum metal surface area for more rapid dissolution of the required amount of metal into water. Once aluminum metal is oxidized by acidic water, the resultant aquated Al.sup.3+ is available to hydrolyze and form larger hydroxyaquoaluminum aggregates.
The reason for adding such stoichiometric excess of aluminum metal, in forming conventional basic aluminum halide materials, can be seen in the following. The reaction stoichiometry for formation of conventional basic aluminum halides can be described by the following reactions: EQU 15H.sub.2 O+5Al+AlX.sub.3 .fwdarw.3Al.sub.2 (OH).sub.5 X+7.5H.sub.2( 1) EQU 12H.sub.2 O+4Al+2AlX.sub.3 .fwdarw.6Al(OH).sub.2 X+6H.sub.2,(2)
where X is a halide.
It can be seen that in reaction (1), the aluminum metal to aluminum halide molar ratio is 5:1, and in reaction (2) such molar ratio is 2:1. Reaction equations (1) and (2) represent extremes in commercial basic aluminum halides. As can be seen, the aluminum metal to aluminum halide molar ratio determines what the end product can theoretically be. The rate of aluminum metal dissolution into water strongly influences what the end product actually will be. In each case, in order to ensure formation of the desired end product within a commercially feasible time frame, the actual aluminum metal to aluminum halide molar ratio used commercially is larger than that required by the reaction stoichiometry represented by the above reaction equations. Typically, this molar ratio of actual aluminum metal to aluminum halide, in commercial systems, will vary between 3:1 and 10:1.
As can be seen in the foregoing, the important feature in forming conventional basic aluminum halide material is to achieve rapid solubilization of the aluminum metal (as discussed in the above, for example, by adding a level of aluminum metal in excess of that required by reaction stoichiometry). Larger aluminum metal surface areas, for example, by use of aluminum powders, would also permit achievement of relatively rapid solubilization of the aluminum. Thus, for example, use of aluminum powders would permit use of lower molar ratios. Unfortunately, aluminum metal powder is hazardous to handle, and can be explosive if proper precautions are not taken.
U.S. patent application Ser. No. 07/518,516, now U.S. Pat. No. 5,202,115, issued Apr. 13, 1993, which is a continuation-in-part application of U.S. patent application Ser. No. 07/233,008, filed Aug. 17, 1988 (the contents of the continuation-in-part application and the contents of Ser. No. 07/233,008 each being incorporated herein in their entirety), discloses basic aluminum antiperspirant active materials (polymeric aluminum materials) having the empirical formula: Al.sub.2 (OH).sub.6-a X.sub.a, where 0.5.ltoreq.a.ltoreq.5.0, and X is a univalent complex oxoanion of nitrogen or halogen, such as NO.sub.3.sup.-, ClO.sub.3.sup.-, ClO.sub.4.sup.- and IO.sub.4.sup.-, the antiperspirant active material being further characterized by:
(a) Size exclusion high performance liquid chromatography (HPLC) peaks corresponding to peak 3 and peak 4 of the size exclusion chromatogram produced from a high performance liquid chromatography technique;
(b) A peak 4 relative area of at least 25%, and a peak 3 relative area of less than 60%, the sum of the relative peak 3 and peak 4 areas being at least 50%; and
(c) Less than 10% chromatographic peaks eluting at shorter retention times (or larger molecular sizes) than the peak 3, corresponding to peaks 1 and 2.
This continuation-in-part application discloses that the basic aluminum materials described therein can be produced at relatively low temperatures, such as at temperatures below 45.degree. C., with the time of heating in the temperature range of 45.degree. C.-140.degree. C. being 0.5-17 hours. This continuation-in-part application discloses that the basic aluminum materials described therein can be formed at lower temperatures, and/or in smaller amounts of time, and at higher initial aluminum solution concentrations, than when using techniques for forming conventional basic aluminum halide materials having enhanced antiperspirant activity.
This continuation-in-part application discloses that the described basic aluminum material can be formed by dissolving an aluminum salt of the univalent complex oxoanion in water, heating, and (while heating) adding additional aluminum in metallic form. Where the aluminum salt is an aluminum nitrate, the reaction scheme for forming the basic aluminum material in the foregoing continuation-in-part application is described as follows: EQU 58H.sub.2 O+28Al+16Al(NO.sub.3).sub.3 .fwdarw.22Al.sub.2 (OH).sub.5 NO.sub.3 +26NO+3H.sub.2,
where the production of nitric oxide represents a reduction of the nitrate oxoanion from a formal +7 to +2 oxidation state on the nitrogen atom. This continuation-in-part application also discloses that the aluminum salt of the univalent complex oxoanion can be formed in situ, by reacting aluminum metal with, e.g., an inorganic acid of the univalent complex oxoanion.
Consistent with techniques in connection with conventional basic aluminum halide materials, this continuation-in-part application describes forming the described basic aluminum material having the univalent complex oxoanion by adding small turnings of aluminum metal in the form of oblong pieces 1/16 inch to 1/8 inch long and 1/100 inch to 3/100 inch thick, in excess, to a solution of monomeric aluminum ion and univalent complex oxoanion.
This continuation-in-part application also discloses a basic aluminum antiperspirant material having enhanced efficacy, wherein such material contains at least 25% by weight of the aluminum in the form of Al.sup.b polyhydroxyaquoaluminum. This continuation-in-part application discloses that, typically, the antiperspirant active material contains up to 50% by weight of the total aluminum in the form of Al.sup.b polyhydroxyaquoaluminum.
While the continuation-in-part application, and application Ser. No. 07/233,008, describe basic aluminum antiperspirant materials containing univalent complex oxoanions, having enhanced antiperspirant activity, which can be provided directly (that is, without previously forming a basic aluminum material and then heating) at relatively low temperatures and which are relatively stable, it is still desired to provide basic aluminum materials having improved antiperspirant activity and which can be provided utilizing a relatively safe and inexpensive technique, in a relatively short period of time.
U.K. patent Application Ser. No. 2,048,229 describes a group of complexes (Al.sup.c') within the aluminum chlorhydroxides which are more efficacious as an antiperspirant. Such group Al.sup.c' complexes with a ferron reagent at a reaction rate characteristic of Al.sup.c (of Al.sup.a, Al.sup.b and Al.sup.c, Al.sup.c is the group that exhibits the slowest complexing reaction ratio with ferron), and has a permeation rate in gel permeation chromatography which is within that range generally found for Al.sup.b (of Al.sup.a, Al.sup.b and Al.sup.c, Al.sup.b has an intermediate retention time, indicating it includes complexes of intermediate molecular size). This U.K. patent application describes that the Al.sup.c' group of complexes was present in amounts of 10%-30% by weight in then-available aluminum chlorhydroxides, and that these then-available aluminum chlorhydroxides can be modified to contain substantially larger amounts of the Al.sup.c' group. This patent application discloses a technique to increase the amount of the Al.sup.c' group, by aging then available (commercial) aluminum chlorhydroxide.
This U.K. Patent Application does not disclose use of basic aluminum materials having a univalent complex oxoanion of nitrogen or a halogen, does not describe direct preparation of the basic aluminum material (rather, disclosing aging of then available aluminum chlorhydroxide), and does not achieve the advantages of the present invention.
European Patent Application No. 191,628, the contents of which are incorporated herein by reference in their entirety, discloses a direct process of making a basic aluminum halide in powder form having an aluminum:halogen molar ratio of from 1.7 to 2.2:1 and having at least 20% of the aluminum contained in a Band III fraction. This process includes steps of:
(a) dissolving metallic aluminum in an aqueous starting solution of an aluminum compound selected from aluminum chloride and aluminum bromide, the starting solution being held at a temperature of about 50.degree. C. to about 105.degree. C., for a time just long enough to dissolve sufficient aluminum to produce an aqueous solution of a final basic aluminum halide having an aluminum:halide molar ratio in the range 1.7:1 to 2.2:1, the concentration of the aluminum in the starting solution and the amount of aluminum dissolved being such that the aluminum concentration in the solution of the final basic aluminum halide is from 0.8% to 6.75% by weight, and the final basic aluminum halide having at least 20% of the aluminum contained in the Band III fraction; and
(b) drying the solution of the final basic aluminum halide so as to give the final basic aluminum halide in the form of a hydrated powder having at least 20% of the aluminum contained in the Band III fraction.
European Patent Application No. 191,628 further discloses that in the direct preparative procedure for forming the described basic aluminum halide material, under some conditions products containing a high proportion of the aluminum in the Band III species contain a substantial proportion of this component in the form of a polymer having a characteristic line in the .sup.27 Al NMR (nuclear magnetic resonance) spectrum. This patent application discloses this characteristic line is 62.5 ppm downfield from the resonance of Al.sup.3+ (6H.sub.2 O), and has been attributed to a complex aluminum ion referred to as the Al.sub.13 O.sub.40 ion. In one embodiment of the disclosed process, at least 20% of the aluminum of the final basic aluminum compound is in the form of the Al.sub.13 O.sub.40 ion.
European Patent Application No. 285,282 discloses antiperspirant materials, including partially neutralized aluminum salts, the salts having at least 25% of the total aluminum present in a form having a .sup.27 Al NMR spectrum wherein 8% to 25% of the total area under the spectrum from 140 ppm to -80 ppm is contained in a peak at approximately 63 ppm (corresponding to tetrahedrally co-ordinated aluminum ions). This European patent document discloses a technique for forming the described aluminum salt, by partially neutralizing an aqueous acid (such as a mineral acid) using a source of aluminate ion (the mineral acid optionally being an aluminum salt), with no subsequent heating step required. Specifically embodied in this patent document are aluminum halohydrate materials, such as aluminum chlorhydrate; the disclosed aluminum chlorhydrate has an increased proportion of smaller species and is deficient in the larger polymeric species.
While each of European Patent Application No. 191,628 and No. 285,282 describe direct techniques for forming a basic aluminum antiperspirant material, each of these patent documents are primarily directed to halide materials. Moreover, European Patent Application No. 285,282 discloses halide and nitrate materials formed by reacting an aluminate with, e.g., an aluminum salt, rather than use of aluminum metal to react with an aluminum salt. Neither of these European patent applications disclose basic aluminum compounds as in the present invention, having enhanced antiperspirant activity, which can be manufactured by a relatively safe and inexpensive technique.
It is also desired to provide an antiperspirant composition including a basic aluminum material containing a univalent complex oxoanion and another antiperspirant active material, and a method of producing such composition.
The aforementioned continuation-in-part U.S. patent application, filed May 2, 1990, and its parent application Ser. No. 07/233,008, filed Aug. 17, 1988 (the contents of each of which have previously been incorporated herein by reference in their entirety) disclose incorporating the described basic aluminum antiperspirant material with enhanced antiperspirant activity, having a univalent complex oxoanion, in a composition including another antiperspirant active compound (for example, a compound containing a metal cation selected from Zr, Hf, Ti or Sn), such composition containing (or not containing) a neutral amino acid. The patent applications disclose that the composition can be prepared by simple mixing of a solution of the basic aluminum material having enhanced antiperspirant activity with a solution of the Zr, Hf, Ti and/or Sn material (for example, a solution of zirconyl hydroxychloride), the temperature of such mixing being at least room temperature, and, illustratively, at a temperature of 45.degree.-140.degree. C. The patent applications disclose that the composition can be provided without dilution and/or heating, and thus is more stable in water as compared to corresponding compositions using aluminum chlorhydrate of enhanced antiperspirant activity.
U.S. Pat. No. 2,814,585 to Daley discloses an antiperspirant composition including in combination an aqueous solution of a zirconium or hafnium salt of a strong monobasic mineral acid, a basic aluminum compound, and an amino acid in which the number of amino groups is equal to the number of carboxyl groups in the molecule (that is, neutral amino acids). This patent discloses that the basic aluminum compounds and the amino acids act as buffering agents to bring the pH of the solution of the zirconium or hafnium salt to a value which renders it safe for antiperspirant usage. This patent discloses that the basic aluminum compounds with which the hafnium and zirconium salts, and neutral amino acids, are combined have the general empirical formula Al.sub.2 (OH).sub.6-n X.sub.n, where X is a monovalent acid anion of the group Cl.sup.-, Br.sup.-, I.sup.- and NO.sub.3.sup.-, and n has an average value from about 0.8 to about 2.
U.S. Pat. No. 4,331,609 to Orr discloses antiperspirant compositions which are non-irritating to the skin and which are non-damaging to textiles, the compositions including an aluminum compound, a zirconium compound, a neutral amino acid and an inorganic acidic compound. This patent discloses that the aluminum compound has the empirical formula Al.sub.2 (OH).sub.6-n X.sub.n, wherein n has a value of from about 0.80 to about 1.25 and X is selected from the group consisting of chlorine, bromine, iodine, sulfamate, sulfate, nitrate and mixtures thereof.
While each of U.S. Pat. Nos. 2,814,585 and 4,331,609 disclose antiperspirant compositions including a basic aluminum compound containing a univalent complex oxoanion (e.g., nitrate), neither of these patents disclose that the basic aluminum nitrate is a nitrate having enhanced antiperspirant activity, much less compounds having specific NMR spectra and/or form. Moreover, these patents do not disclose achieving further enhanced activity, based on specific techniques for forming the compounds. In addition, these patents teach that the nitrates therein are equivalent to, e.g., the chlorides.
U.S. Pat. No. 4,775,528 to Callaghan, et al discloses an antiperspirant composition having high antiperspirant efficacy, comprising zirconyl hydroxychloride and aluminum chlorhydroxide in which the atomic ratio of Al to Zr is from 6:1 to 1:1, such composition (when dissolved in water to form a 10% by weight solution and, after storage at room temperature for no more than two hours, subjected to gel permeation chromatography on cross-linked dextran having a molecular weight exclusion range of 1,000 to 30,000 for globular proteins (Sephadex G-50)) exhibiting a distribution pattern having peaks at Kd=0.7 and Kd=0.5 in which the ratio of the height of the first peak to that of the second is at least 1.5:1. This patent also discloses a method of making such composition, wherein a 2%-18% solution of aluminum chlorhydroxide in water is heated at a temperature of at least 50.degree. C. with the zirconyl hydroxychloride being mixed therewith before, during or after the heating step, the amount of the zirconyl compound being sufficient to provide an atomic ratio of Al:Zr from 6:1 to 1:1, the heating being continued until the above-referred-to distribution pattern is achieved. This patent further discloses that the composition can optionally also include a neutral amino acid. With reference to FIG. 1 of U.S. Pat. No. 4,775,528, this patent teaches that peak 1 of the chromatogram of the composition (peak 1 being the first eluted fraction) contains the zirconium compound; that peak 2 contains the Al.sup.c complex; that peak 3, at Kd=0.5, contains the Al.sup.c' complex; and that peak 4, at Kd=0.7, which appears only as a shoulder between peaks 3 and 5, contains a hitherto unrecognized novel complex which is present only in a small proportion, while peaks 5 and 6 are fractions containing Al.sup.a or other lower molecular weight compounds.
This patent does not teach or suggest compositions including basic aluminum materials, having enhanced antiperspirant activity, containing univalent complex oxoanions, as in the present invention. Moreover, this patent does not teach or suggest the amount of the basic aluminum compound in the form of Al.sup.b, or the .sup.27 Al NMR spectrum, as in the present invention.
U.S. Pat. No. 4,606,915 to Rosenberg, et al discloses that a composition of a stannic halide and an aluminum halohydrate, and also preferably containing a neutral amino acid, is useful in inhibiting perspiration when applied to the skin of a subject in powder form or when incorporated in a liquid or solid vehicle. In this patent, there is no disclosure that the aluminum compound has enhanced activity, nor that the resultant basic tin/aluminum halohydrate demonstrates enhanced antiperspirant activity. The contents of U.S. Pat. No. 4,606,915 are incorporated herein by reference in their entirety.
Accordingly, it is still desired to provide basic aluminum materials with further enhanced antiperspirant activity; and compositions of (1) zirconium, hafnium, tin and/or titanium active antiperspirant material, either those conventionally known or those having enhanced antiperspirant activity, with (2) basic aluminum material having further enhanced antiperspirant activity, which materials and compositions can be made inexpensively and safely, and which are stable after being formed. It is also desired to make such basic aluminum materials and such compositions, without the necessity of using high temperatures and/or high pressures, and without the need for extra manufacturing steps of heating diluted solutions of already manufactured basic aluminum compounds. It is also desired to provide such materials and compositions in concentrated aqueous solutions.